Nationality is the legal relationship between a person and a state.[1] Nationality affords the state jurisdiction over the person and affords the person the protection of the state. What these rights and duties are vary from state to state.[2]

Nationality differs technically and legally from citizenship, which is a different legal relationship between a person and a country. The noun national can include both citizens and non-citizens. The most common distinguishing feature of citizenship is that citizens have the right to participate in the political life of the state, such as by voting or standing for election. However, in most modern countries all nationals are citizens of the state, and full citizens are always nationals of the state.[1][4]

In international law, nationality is the status or relationship that gives a nation the right to protect a person from other nations.[4] Diplomatic and consular protection are dependent upon this relationship between the person and the state.[4] A person's status as being the national of a country is used to resolve the conflict of laws.[5]

Nationality is also the status that allows a nation to grant rights to the subject and to impose obligations upon the subject.[4] In most cases, no rights or obligations are automatically attached to this status, although the status is a necessary precondition for any rights and obligations created by the state.[5]

Within the broad limits imposed by few treaties and international law, states may freely define who their nationals are and are not.[4] However, since the Nottebohm case, other states are only required to respect their claim to protect an alleged national if the nationality is based on a true social bond.[4] In the case of dual nationality, states may determine the most effective nationality for a person, to determine which state's laws are most relevant.[5] There are also limits on removing a person's status as a national. Article 15 of the Universal Declaration of Human Rights states that "Everyone has the right to a nationality," and "No one shall be arbitrarily deprived of his nationality nor denied the right to change his nationality."

Nationals normally have the right to enter or return to the country they belong to. Passports are issued to nationals of a state, rather than only to citizens, because the passport is the travel document used to enter the country. However, nationals may not have the right of abode (the right to live permanently) in the countries that grant them passports.

Historically, the most significant difference between a national and a citizen is that the citizen has the right to vote for elected officials, and to be elected.[4] This distinction between full citizenship and other, lesser relationships goes back to antiquity. Until the 19th and 20th centuries, it was typical for only a small percentage of people who belonged to a city or state to be full citizens. In the past, most people were excluded from citizenship on the basis of gender, socioeconomic class, ethnicity, religion, and other factors. However, they held a legal relationship with their government akin to the modern concept of nationality.[4]

Nationality is sometimes used simply as an alternative word for ethnicity or national origin, just as some people assume that citizenship and nationality are identical.[7] In some countries, the cognate word for nationality in local language may be understood as a synonym of ethnicity or as an identifier of cultural and family-based self-determination, rather than on relations with a state or current government. For example, some Kurds say that they have Kurdish nationality, even though there is no Kurdish sovereign state at this time in history.

A Soviet birth certificate, in which the nacional'nost' of both parents (here both Jewish) was recorded. These records were subsequently used to determine the ethnicity of the child, as specified in his internal passport.

In the context of former Soviet Union and former Socialist Federal Republic of Yugoslavia, "nationality" is often used as translation of the Russiannacional'nost' and Serbo-Croatiannarodnost, which were the terms used in those countries for ethnic groups and local affiliations within the member states of the federation. In the Soviet Union, more than 100 such groups were formally recognized. Membership in these groups was identified on Soviet internal passports, and recorded in censuses in both the USSR and Yugoslavia. In the early years of the Soviet Union's existence, ethnicity was usually determined by the person's native language, and sometimes through religion or cultural factors, such as clothing.[8] Children born after the revolution were categorized according to their parents' recorded ethnicities. Many of these ethnic groups are still recognized by modern Russia and other countries.

National identity is a person's subjective sense of belonging to one state or to one nation. A person may be a national of a state, in the sense of having a formal legal relationship with it, without subjectively or emotionally feeling a part of that state. Conversely, a person may feel that he belongs to one state without having any legal relationship to it. For example, children who were brought to the U.S. illegally when quite young and grow up there in ignorance of their immigration status often have a national identity of feeling American, despite legally being nationals of a different country.

Dual nationality is when a single person has a formal relationship with two separate, sovereign states.[6] This might occur, for example, if a person's parents are nationals of separate countries, and the mother's country claims all offspring of the mother's as their own nationals, but the father's country claims all offspring of the father's.

Nationality, with its historical origins in allegiance to a sovereign monarch, was seen originally as a permanent, inherent, unchangeable condition, and later, when a change of allegiance was permitted, as a strictly exclusive relationship, so that becoming a national of one state required rejecting the previous state.[6]

Dual nationality was considered a problem that caused conflict between states and sometimes imposed mutually exclusive requirements on affected people, such as simultaneously serving in two countries' military forces. Through the middle of the 20th century, many international agreements were focused on reducing the possibility of dual nationality. Since then, many accords recognizing and regulating dual nationality have been formed.[6]

Statelessness is the condition in which an individual has no formal or protective relationship with any state. This might occur, for example, if a person's parents are nationals of separate countries, and the mother's country rejects all offspring of mothers married to foreign fathers, but the father's country rejects all offspring born to foreign mothers. Although this person may have an emotional national identity, he or she may not legally be the national of any state.

^ abcVonk, Olivier (March 19, 2012). Dual Nationality in the European Union: A Study on Changing Norms in Public and Private International Law and in the Municipal Laws of Four EU Member States. Martinus Nijhoff Publishers. pp. 19–20. ISBN90-04-22720-2.

White, Philip L. (2006). What is a nationality?, based on "Globalization and the Mythology of the Nation State," in A.G.Hopkins, ed. Global History: Interactions Between the Universal and the Local Palgrave Macmillan, pp. 257–284

Article 29.3: The supremacy of the purposes and principles of the United Nations

Article 30:

Nothing in this Declaration may be interpreted as implying for any State, group or person any right to engage in any activity or to perform any act aimed at the destruction of any of the rights and freedoms set forth herein.